1. Field of the Invention
The present invention relates to a pointer display apparatus and method using a virtual region and, more particularly, to a pointing apparatus and method and a pointer display apparatus and method using a virtual region which generate a virtual region corresponding to a detected display region, convert coordinates of a location, which is pointed at by the pointing device, in the virtual region into coordinates of the location in the display region, and display a pointer at the converted coordinates.
2. Description of the Related Art
Direct pointing devices are input devices which can extract the display region of a display device such as a digital television (TV), detect the location of a portion on the screen currently being pointed at by a pointer, and control the location of the pointer displayed on the screen of the display device according to the results of the detection.
Direct pointing devices use a direct mapping method by which a pointer is displayed at a place pointed at by a user and thus can manipulate the location of a pointer more quickly and easily than pointing devices such as mice or keypads which use a relative mapping method. Also, direct pointing devices can allow a user to control the location of a pointer from a distance.
However, if a pointer is displayed in a display region of a display device using a direct pointing device, a user may have difficulty determining the location of the pointer as the distance between the display device and the direct pointing device increases.
FIG. 1 is a view for illustrating a method of displaying a pointer using a conventional direct pointing device 20a or 20b. Specifically, FIG. 1 illustrates an effective angle 25a or 25b of the direct pointing device 20a or 20b, respectively, which allows the pointer to be displayed in a display region 15 of a display device 10 according to the distance between the display device 10 and the direct pointing device 20a or 20b. 
In other words, when the direct pointing device 20a is located a short distance away from the display device 10, directions in which the direct pointing device 20a points (hereinafter referred to as pointing directions) are within a relatively wide angle range. Conversely, when the direct pointing device 20b is located further from the display device 10, the pointing directions of the direct pointing device 20b are within a narrower angle range.
Therefore, when displaying the pointer in the display region 15 using the direct pointing device 20a at a short distance from the display device 10, a user can determine the location of the pointer in the display region 15 without much difficulty. However, when displaying the pointer in the display region 15 using the direct pointing device 20b at a long distance from the display device 10, the user may have difficulty determining the location of the pointer. In other words, since a slight change in the pointing direction results in a great change in the location of the pointer, the user cannot precisely change the location of the pointer and may have more severe hand shaking.
Korean Patent Publication No. 2005-083723 discloses a cursor for electronic devices. In this publication, a correlation between the cursor location in a display region and the location of a displayed part of a virtual region within the whole virtual region is determined so that the cursor location in the display region reflects the location of the displayed part of the virtual region in proportion to the whole virtual region.
The above invention is used to search a particular virtual region within the whole virtual region that exceeds the range of the display region, but does not disclose a method of determining the location of a pointer according to the position of a user.
Therefore, it is required to develop a method by which a user can easily determine the location of a pointer regardless of the distance between a display device and a pointing device.